There have been vehicle air-conditioning apparatus in which even when on the basis of a target outlet temperature foot mode delivery has been selected, if the amount of solar radiation detected by a solar radiation level sensor exceeds a predetermined level, a switch is made to bi-level mode delivery.
For example, in JP-B-60-21887, an air-conditioning apparatus is disclosed which has switching means for switching in accordance with thermal load conditions expressed with a target outlet temperature between vent mode delivery, whereby air is delivered to the upper part of a passenger compartment; foot mode delivery, whereby air is delivered to a lower part of the passenger compartment; and bi-level mode delivery, whereby vent mode delivery and foot mode delivery are implemented at the same time, and a solar radiation level sensor. Also disclosed is technology whereby even when foot mode delivery has been selected by this switching means, if strong solar radiation is entering the passenger compartment, on the basis of a detection signal of a solar radiation level sensor for sensing hotness caused by solar radiation, bi-level mode delivery is selected, and a cool draft is delivered from an upper side of the outlet to an upper part of the inside of a passenger compartment to eliminate the hotness caused by the solar radiation.
However, depending on the positional relationship between the vehicle body and the sun, the body of an occupant exposed to solar radiation entering the passenger compartment may be partly in the shade of the roof and pillars of the vehicle body. And, because the solar radiation level sensor is normally disposed near the middle of the front of the top face of an instrument panel, the solar radiation level detected by the solar radiation level sensor does not always reflect the level of solar radiation to which the occupant is actually exposed.
FIG. 10A and FIG. 10B are views showing differences in the solar radiation received by an occupant and the solar radiation received by a solar radiation level sensor resulting from the positional relationship between the vehicle body and the sun. FIG. 10A shows the sun positioned in front of the vehicle, and FIG. 10B shows the sun positioned slightly behind directly above the vehicle.
As shown in FIG. 10A, when the sun 100 is positioned in front of a vehicle body 101, rays from the sun reach both a solar radiation level sensor 103 and the upper body of an occupant 104 at the same time, through a front windshield 102.
On the other hand, as shown in FIG. 10B, when the sun 100 is slightly behind directly above the vehicle body 101, whereas rays from the sun 100 reach the solar radiation level sensor 103 through the front windshield 102, rays from the sun 100 approaching the occupant 104 are blocked by a roof 105 and do not reach the occupant 104.
Thus, depending on the positional relationship between the vehicle body 101 and the sun 100, cases arise where notwithstanding that the sun's rays are reaching the solar radiation level sensor 103 in the same way, the amount of sunlight (solar radiation) reaching the occupant 104 differs.
Consequently, it sometimes happens that even though an occupant is in the shade of the vehicle body (the roof or a pillar) and is not feeling hotness, if the solar radiation level sensor detects a predetermined level of solar radiation (intensity of the sun's rays), the outlet is switched to bi-level and a cool draft is delivered. In this case, because the occupant is exposed to a cool draft despite not being exposed to solar radiation, the occupant feels cold. In this way, depending on the position of the sun and the positional relationship of the vehicle body and the occupant, there has been the problem that a mismatch arises between the switching of outlets and the feeling of the occupant.
Consequently, a way has been awaited of switching to a mode matched to the feeling of the occupant with respect to the sun.